This invention relates to quartz crystal wrist watches and to the physical structure thereof. Quartz crystal wrist watches are generally provided with a battery power source, a crystal oscillator which serves as a time standard and associated circuitry for converting the output of the oscillator to the desired driving signal, an electro-mechanical converter responsive to said driving signal such as a pulse motor and indexing mechanism, and the drive train of the watch.
These components must be mounted in a watch so as to provide a compact thin structure. Further, although it is more convenience to mount these components in a square watch, there is a larger demand for round wrist watches, thereby complicating the mounting of these structures into a watch case. Thus, the battery power source requires a substantial portion of the space of the wrist watch, and being generally round in shape, occupies a greater space than its volume would otherwise indicate. Further, if other components are mounted above or below the battery, the thickness of the watch would be substantially increased.
The oscillator and associated circuitry includes the crystal oscillator generally mounted in a vacuum in a hermetic sealed case provided with a shield cap and external lead terminal, an oscillation circuit, a fine adjusted mechanism for adjusting the frequency of the oscillator, a temperature compensating element, a divider circuit for dividing the frequency of the output of the crystal oscillator, and a driving circuit for the electromechanical converter. If these components are separately mounted, assembly and repair of the watch becomes difficult and expensive. Further, the method of mounting these components must avoid frequency changes due to stray capacitance and external shock.
By the compact assembly approach of the invention, the foregoing difficulties are solved.